Fuel bladders in an aircraft, either as the primary source of fuel for the aircraft or as a fuel re-supply system, such as in a tanker, are installed as a secondary system held in place by lacing. A variety of interconnects may attach to the bladder. Examples of interconnects include fuel lines, fill ports, access ports, vents, and cell leveling ports allowing flow between cells of a fuel bladder.
To facilitate connection of an interconnect to a fuel bladder, a rigid metal, such as aluminum, interconnect ring is bonded and clamped onto a flat section of bladder material. The bladder material has a central opening. An opening through the interconnect ring is aligned with the central opening. Excess bladder material surrounding the ring may function as a flange for bonding the assembly to a fuel bladder over an opening through a wall of the fuel bladder. The assembly allows access into the fuel bladder through the interconnect ring. The interconnect ring is connected to the interconnect which is, in turn, anchored into the fuselage structure of the aircraft.
The interconnect anchors may be rigid in nature compared to the flexibility of some fuel bladders. Movement of the fuel bladder can apply a load to the interconnect and/or a back-up structure providing support for the interconnect. Also, while sufficiently low manufacturing tolerances may allow proper fit of a bladder, slightly undersized measurement may create installation difficulty and apply a load to the interconnect. The applied loads can cause failures leading to fuel leaks and costly repairs. It is possible to improve aircraft having fuel bladders to avoid damage to interconnects and/or fuel bladders resulting from fuel bladder movement.